Underwater wellhead flow line connector



y 1963 R. GEER 3,090,437

UNDERWATER WELLHEAD FLOW LINE CONNECTOR Original Filed Aug. 25, 1959 3Sheets-Sheet 1 FIG. I

INVENTORI R. L. GEER HIS AGENT May 21, 1963 R. L. GEER 3,090,437

UNDERWATER WELLHEAD FLOW LINE CONNECTOR Original Filed Aug. 25, 1959 3Sheets-Sheet 2 HIS AGENT May 21, 1963 R L. GEER UNDERWATER WELLHEAD FLOWLINE CONNECTOR Original Filed Aug. 25, 1959 3 Sheets-Sheet 5 v oE m R CE H1 m L I N H mm mm mm o: R JV V E .5 mm g B m mm m mm a R f/ fiuhlluFF 2v m 2 m umm fiV 7/4 o- R: dAX// m9 United States Patent A O 13Claims. (Cl. 166-665) The present apparatus relates to oil wellequipment for use at underwater locations and pertains more particularlyto an underwater wellhead apparatus with a remotelydetachable flow linewhich includes a power-actuated and remotely-operable pipeline connectorfor connecting the wellhead assembly to an underwater pipeline, such asone running along the ocean floor.

The wellhead apparatus of the present invention is adapted to be used toclose wellhead assemblies of the type described in copending patentapplication, Serial No. 834,096, filed August 17, 1959, now Patent No.3,064,- 735. A recent development in the field of oil well drilling isthe completion of wells at offshore locations with a wellhead assemblypositioned on or close to the ocean floor out of the way of ships whichmight otherwise damage it in the event of a collision. Equipmentpositioned on the ocean floor, however, is exposed to conditions such asthe corrosive nature of the sea water and the presence of marine lifewhich tends to grow and become encrusted on metallic structures belowthe surface of the water.

Since it is necessary from time to time to go back into a Well whereverit has been completed for servicing or work-over operations, it isdesirable to have an underwater wellhead structure of suitable design sothat it could be readily removed from the underwater wellhead and raisedto the surface. An underwater wellhead structure of this type is shownand described in copending patent application, Serial No. 834,096, filedAugust 17, 1959.

On removing a wellhead assembly from the topof the well in accordancewith present practice, a diver must first be sent to the ocean floor todisconnect the production flow line from the wellhead assembly.Otherwise, the production flow line adjacent the wellhead assembly mustbe raised to the surface of the water along with the wellhead assemblywhen the latter is removed from an underwater wellhead and raised to thesurface. Divers can be used efiectively only at relatively shallow waterdepths of up to about 150 feet.

An object of the present invention is to provide a remotely-controlledhydraulically-operated pipeline coupling device for use in connecting anunderwater pipeline to an underwater wellhead assembly which closes anoffshore well and controls the production of fluid therefrom.

A still further object of the present invention is to provide aremotely-controlled hydraulically-operated pipeline connector for use inconnecting underwater pipelines to an underwater wellhead assembly, withthe pipeline connector being provided with sealing means and lockingmeans that are carried internally within the coupling so .as to minimizeor substantially eliminate corrosion and the growth of marine organismson the metallic working portions of the coupling.

Still another object of the present invention is to provide aremotely-controlled hydraulically-operated pipeline coupling for usebetween an underwater pipeline and a wellhead assembly, wherein thesealing and locking elements of the coupling are carried by one-half ofthe coupling and are actuated successively by the application of asingle pressure fluid thereto.

These and other objects of the present invention will be 'wardly. IPreferably,

understood from the following description taken with regard to thedrawing, wherein:

FIGURE 1 is a schematic view assembly of the floor; 7

FIGURE 2 is a side view of the pipeline coupling lowering mechanismshown in FIGURE 1; and,

FIGURES 3 and 4 are views taken in longitudinal crosssection of ahydraulically-operated pipeline connector or coupling, of the type to beused with the wellhead assembly of FIGURE 1, in its uncoupled andcoupled positions, respectively.

Referring to FIGURE 1 of the drawing, port structure 11 is shown ascomprising a series of interconnected girders 12 and cross-bracingmember 13. The bottom-most girders 12 may rest on a cement pad 14 whichmay be poured on the ocean floor in a manner described in copendingpatent application, Serial No. 830,538, filed August 30, 1959. Acasinghead 15 is fixedly secured to the wellhead support structure 11and is preferably installed therewith at the time the wellhead supportstructure is positioned over the well to be drilled.

Suitableapparatus is provided for guiding well equipment into place uponthe casinghead 15, both during and after drilling operations. In theparticular apparatus illustrated in FIGURE 1, the vertical members 17 ofthe wellhead support structure comprise vertical guide tubes 17 eachhaving a vertical slot 18 cut through the Wall thereof. Each piece ofequipment to be lowered into place on the well casinghead 15 may beprovided with two or more guide arms 21 adapted to extend through theguide slot 18 of two or more guide tubes 17 where they are connected toguide cones 22. The guide cones are ofa diameter slightly less than theinner diameter of the guide tubes 17 and preferably have a lower portionthat tapers downillustrating a wellhead present invention positioned onthe ocean a wellhead supeach of the guide tubes 17 has a cone-shapedflange 23 attached to its upper end which serves to align the guidecones 22 as they move downwardly into the guide tubes 17. Each of theguide cones 22 is provided with a vertical hole therethrough of adiameter slightly larger than the guiding cables 24 which are secured attheir ends to the wellhead support structure within, the bottom oftheguide tubes 17 and extend upwardly to the surface where they aresuspended from a drilling vessel or barge (not shown) from whichoperations are being carried out. I

In FIGURE l'the guide arms 21 are shown as being connected to acontainer 25 which may be employedto surround the wellhead assembly orproduction control unit of the well. For purposes of simplifying thedrawing .and description thereof, the wellhead assembly of the presentinvention is shown as comprising a pair of control valves 26 and 27which are positioned in the production flow line 23 coming from thewell. thewell is illustrated; as having a single string of well casing30 and a single string of production tubingj31 extending downwardly intothe well, it is to be understood that the present wellhead apparatuscould be employed with Wells having multiple strings of casing andtubing.

Normally, the production control unit or wellhead assembly enclosedwithin the container 25 comprises the necessary piping, valves, chokes,and other equipment normally connected together and mounted on the topof a well, and known as a Christmas tree, together with the necessaryhydraulic or electrical systems including pumps, reservoirs, motors, andetc., to operate the valves at the head of the well from a remotelocation. A typical example of a suitable underwater production controlunit or wellhead assembly for use at an offshore well location, and themanner in which it is locked to the 3 casinghead 15, is shown anddescribed in copending patent application, Serial No. 834,096, filedAugust 17, 1959.

The container 25 and the wellhead, assembly contained therein isnormally lowered into place by means of a string of pipe $2 known as arunning string which has a running head 33 attached to the lower endthereof which may be connected to the top of container 25 or to itslubricator 34, The lubricator or wellhead closure 34 may be of anydesired type suitable for use in offshore underwater wellheadassemblies. A typical lubricator or wellhead closure of this type isshown and described in copending application, Serial No. 830,587, filedAugust 30, 1959, now abandoned. A wellhead closure of this type permitsre-entry into the well for well control or workover purposes. Duringnormal production of a well the running string 32, running head 33 andany pressure tubing strings 35 and 36 which may be contained therein,are disconnected from the wellhead assembly and drawn to the surface.When not in use the guide cables 24 are dropped to the ocean floor wherethey may later be retrieved by grappling hooks or other suitable meanswhen it is desired to use them again to lower equipment to the wellhead.During work-over or. other operations on the well, the running string 32and the running head 33' may be replaced by a marine conductor pipestring and a landing head or seal (not shown).

The production flow line 28 as it leaves the top of the wellheadassembly or the container 25 is preferably, though not necessarily,curved in an arc of substantial radius so that various tools,instruments, or other devices may be circulated through the productionflow line and down into the well. As the flow line 28 passeshorizontally by the container 25 it is preferably rigidly fixed theretoas by welding, clamping, bolting, etc.

A pipeline coupling or a pipeline connector consisting of a femaleportion 40 and a male portion 41 is installed in the production flowline 28 at a point close to the wellhead assembly or its container 25.Preferably, the male portion 41 of the coupling is fixedly mounted on acarriage 42 which is, in turn, fixedly secured by means of suitablebraces 43, 44 and 45 (FIGURE 2) to one or more guide cones 46 and 47.The guide cones 46 and 47 are slidably mounted on a guide cable 48 whichpasses downwardly through a vertical guide tube 51 which is similar indesign to guide tubes 17 and is provided with a slot 52 therein and acone-shaped flange 53 on the top thereof. A suitable stop member isprovided in the guide tube 51 so as to limit the downward movement ofthe cones 46 and 47 within the guide tube 51 so that the carriage 42, atthe end of its travel, is positioned with the male portion 41 of thecoupling on a level with the female portion 40. Instead of employing astop member within the guide tube 51, the slot 52 therein could beterminated at some point above the bottom of the tube 51 so as to limitthe downward travel of the lower guide cone 47.

The precise placement of the slot 52 in the guide tube 51 serves asaligning means between the carrier 42 and the cable 48 to position themale .portion 41 of the coupling in substantially coaxial register andspaced relationship with the female portion 40 of the coupling. In someinstallations it may be found more advantageous to lower the maleportion 41 of the coupling on its carriage 42 that is suspended betweentwo parallel guide cables 48 which terminate intwo parallel guide tubes51. The portion 28a of the production fiow line extending from the maleportion 41 of the coupling is preferably flexible, but may alsobe apreformed rigid section, to facilitatepositioning it on the ocean floorand attaching it to the female portion 40 of the coupling. In the event,that the well has two or more production flow lines, then the wellheadas sembly would be provided with two or more couplings.

The pipeline coupling ill-41 to he used in connecting the underwaterpipeline 28a to the wellhead. as embly 4 may be of any suitable typewhich is provided with a housing to protect its working parts againstcorrosion caused by the sea water and the growth of marine organisms.The connector 4tl-41 is preferably positioned sub stantiallyhorizontally, i.e., up to about 45 degrees from the horizontal, for easein making the connection. Additionally, the pipeline connector of thepresent invention is positioned to one side of the present wellheadassembly so that after the pipeline coupling 40-41 is disconnected,either the male end 41 of the coupling together with its pipeline 28a,or the female end 40 together with the wellhead assembly and container25, can be raised to the surface independently while the other portionof the coupling and its attached equipment remain at the ocean floororintheir original position. The coupling 40-41 is of the power-actuated,remotely-operated type which may be of either the pneumatic, hydraulic,or electrical type with the power leads or fluid-pressure operatinglines running independently to the surface. However, the coupling 40941is preferably of the remotely-controlled, hydraulically-operatedpipeline coupling as shown in FIGURES 3 and 4 of the drawing. The femaleportion 40 of the coupling contains both the sealing and lockingmechanism for forming a fluidtight seal with the male portion 41 of thecoupling. The female portion of the coupling comprises a central tubularmember 61 which forms an extension of the production flow line 28 and isfixedly secured thereto as by threads 62. The outer surface of tubularmember 61 is reduced in diameter as at 63 so as to seat the end of asleeve 64 which extends outwardly from the flow line 28. The outersurface of the tubular member 61 is further reduced in diameter, as at65, to provide an annular flow passage 66 which is in communication atone end with the pressure fluid conduit 56. The outer surface of thesleeve 64 and the outer surface of the tubular member 61 and its largestdiameter are fitted flush so as to serve as a guide tube on which atubular or sleeve-type piston 67 is slidably mounted; The inner diameterof the piston 67 is enlarged over a portion of the length thereof inorder to form an annular fluid passage 70 between the inside of thepiston 67 and the outside of the sleeve 64.

The outside wall, forming the chamber in which piston 67 is slidablymounted, is formed by a coaxial sleeve or tubular member 71 which isfixedly secured to the end of the pipe 28 as by threads 79. The innerdiameter of the tubular member 71 is increased over a substantialportion of its length to form an annular fluid passageway 72 between theouter wall of the piston 67 and the inner wall of the tubular member 71.The annular fluid passageway or chamber 72 forms the piston chamber inwhich the head 73 of the piston 67 moves. The length of the chamber 72determines the length of the stroke of the piston 67. Thus, it isapparent that the length of the chamber 72 must be at least equal to thedistance the opposite end 68 of the piston 67 must travel in order to bepositioned in fluidtight engagement Within a recessed portion 74 of themale portion 41 of the coupling.

Extending through the tubular member 71 which forms the cylinder wallfor piston head 73 is a fluid passageway 75 in communication between thepressure fluid line 55 at. one end of the apparatus and the spaceoutside the other end of the tubular member. Extending through asubstantial length of the piston wall 67 is a fluid passageway 76 whichis in communication through a port 77, just below the head 73 of thepiston 67, with the annular fluid chamber 72. The annular flow passage66 is in communication through conduit 78 with the pressure fluid line56 at the end of the coupling. 7

A collar $1, forming a tandem piston head with piston head 73, isfixedly secured, as by threads 82, on the outside of the piston 67 justbelow the tubular member 71, or at a distance from the head 73 of thepiston 67 equal to or slightly greater than the stroke of the piston.Fixedly secured to the outside surface of the annular collar or tandempiston 81 is a cylindrical housing 84 which is also in slidingfluidtight engagement with the end 85 of the'tubular member 71.Preferably, the end 85 of the tubular member 71 is enlarged in diameterfor design purposes so that a collar 81 of substantial thickness may beemployed in order to increase the eflective 'area against which pressurefluid acts, as well as to accommodate the necessary valve and conduitarrangement for unlatching the present coupling.

The piston head 73 moves within a chamber formed by the annular sleeve64 and the tubular member 71. While it is possible to consider theenlarged end 85 of the tubular member 71 to be a piston moving withinthe chamber formed by the cylindrical housing 84 on the outside and thepiston 67 on the inside, for purposes of clarification the enlarged end85 of the tubular member 71 will be considered hereinbelow as thestationary end of a piston chamber since the tubular member is fixedlysecured at 72 to the flow line 28. Thus, the collar 81 will beconsidered to be a tandem piston fixedly secured to and movable withpiston 67, with the outside wall of piston '67 and the inside wall ofhousing 84 forming the piston chamber into which a pressure fluid isapplied to move the piston 67, collar 81 and housing 84 axially alongthe central tubular member 61. A port 88 in the tubular member 71 is incommunication between the fluid passage 75 therethrough and the spaceoutside thereof at the end of chamber 72, whereby a pressure fluid maybe applied to the outer face of the piston 73 for driving it to theright.

The extending portion 86 of a cylindrical housing 84 is enlarged indiameter providing a wall of substantial thickness for containing thelocking mechanism of the present coupling. A portion of the wall of theend 86 of the cylindrical housing 84 is recessed to form a pistonchamber 90 in which an annular piston 91 is slidably mounted. The piston91 is fixedly secured to and slidable with a locking piston 92 which maybe either in ring form or may comprise a plurality of individual lockingelements adapted to engage a plurality of locking dogs 93 which areadapted to be seated in a locking groove 94 formed on the outer surfaceof the male portion of the cow pling, as illustrated in FIGURE 4. Thelocking piston 92 is provided with a downwardly sloping surface 95adapted to engage upwardly sloping surfaces 96 of the dogs 93 forraising the dogs 93 into the wall of the cylindrical housing 86 so thatthe female portion 41 of the coupling can be withdrawn.

The locking dogs or latching members 93 are springloaded in any suitablemanner, as by being provided with spring-like arms 97 which allow thedogs 93 to extend normally through slots 98. A locking head 101 iscarried at the end of the locking piston 92 for locking the dogs 93 inplace in the annular groove 94 of the male portion 41 of the coupling,as shown in FIGURE 4.

In the locked position shown in FIGURE 4 of the drawing, a chamber 102is formed in back of piston 91 between the outer surface of the collar81 and the inner surface of the locking piston 92. At the same timeanother chamber 103 is formed between the collar 81 and the enlarged end85 of the tubular member 71 and between the cylindrical housing 84 andthe piston 67. In the locked position the chambers 102 and 103 are incommunication through fluid passageways 104 and 105 and throughpassageway 108 of a spring-loaded valve 106 which has been forcedinwardly by the face 107 of the male portion 41 of the coupling to bepositioned, as shown in FIGURE 4, so that the passageways 104 and 105are in communication through 108.

The piston 91 is provided with a flow passageway 110 while thecylindrical housing 84 is provided with passage way 111 and the collar81 is provided with passageway 112. These flow passageways 110, 111 and112 form a continuous flow passage so that in the unlatched position thechamber 90 formed on one side of the annular piston 91 is incommunication through flow passageways 110, 111, 112, 76 and 77 with theannular fluid chamber 72. The chamber is also in communication through apassageway 113 through the collar 81, through passageway 114 in thepiston 67 and through port 115 in the annular sleeve 64 so as tocommunicate through annular flow passage 66 and conduit 78 with thefluid pressure line 56. The annular fluid passageway 70 between thepiston 67 and the sleeve 64 is in communication at all times throughport 115 with the annular flow passageway 66 and thence through conduit78 with the pressure fluid conduit 56. The outer surface of the piston67 near the end 68 thereof is provided with suitable sealing means 116,such for example as O-ring seals or rings of packing, which act as aprimary seal between the male and female portions of the coupling. Theinner surface of the cylindrical housing 84, or the outer surface of themale coupling 41, is provided with a seal 120 which closes the spacebetween the housing 84 and the male portion 41 of the coupling in afluid 'ght manner. The ends of the female 40 and the male 41 portions ofthe coupling are bevelled, as at 117 and 118, respectively, to aid inaligning the two portions of the coupling when the female portion isforced toward the male portion.

A connection is made between the male and female portions of thecoupling shown in FIGURE 3 by applying a pressure fluid from anysuitable source through conduit 55. The pressure fluid passes throughfluid passageway 75 and port 88 to exert pressure against pistons 81 and73, respectively, moving them to the right together with the cylindricalhousing 84 and the locking dogs 93'. As the cylindrical housing 84approaches the male portion 41 of the coupling, tapered faces 117 and 118 of the female and male portions of the coupling align the twoportions so that the end 68 of the piston 67, containing the sealingrings 116, moves into and is seated within the recessed opening 74 ofthe male portion 41 of the coupling. The end 6 8 of the piston '67continues to slide into the recessed portion 74 until the face 107 ofthe male portion 41 of the coupling forces the fluid trans-fer valve 106to the left, aligning the conduit 108 therein with conduits 104 and 105.At this time, the looking or latching dogs 93 are positioned over slots98 so they may enter the annular groove 94 in the outer surface of themale portion 41 of the'coupling. With the valve 106 in the positionshown in. FIGURE 4 of the drawing, the continued application of apressure fluid through conduits 55 and 75 and into chamber 103 causespressure to be exerted through conduits 105, 108 and 104 and intochamber 102 where pressure is applied tothe right side of the piston 91causing locking piston 92 to move to the left so that the locking head101 of the locking piston bears against the topof the locking dog 93,thus anchoring it in place.

During the sealing and locking operations of the coupling describedabove, fluid in the annular chamber 72 is exhausted through port 77,passageways 76, 112, 111, 110 and into chamber 90 and thence throughpassageways 116 and 114, port 115 and passageways 66, 7'8 and 56 to thehydraulic fluid reservoir (not shown).

To disengage the coupling shown in FIGURE 4, pressure fluid is appliedthrough conduits 56, 7'8 and 66 and thence through port-115 andpassageways 70, 1 14 and 113 to exert a pressure on the left side ofpiston '91, thus forcing it to the right. As the locking piston 92 isforced to the right, the locking head 101 is removed from the top of thelocking dog 93 and the downwardly sloping face of the locking piston 92engages the upwardly sloping face 96 of the locking dog 93 to raise thespringloaded locking dog 93 into its retracted position, as shown inFIGURE 3 of the drawing. As the piston 91 reaches the end of its travelto the right, the conduit therein is brought into communication with theconduit 111 of the cylindrical housing so that pressure fluid from thechamber 90 flows through passageways 110; 111, 112,

. 7 76 and port 77 to exert a pressure on the underside of the'pistonhead 73, thus causing it to move to the left. As the piston '91 moved tothe right in FIGURE 4 to unlock the dogs 93,,iluid in the chamber 102 isexhausted through fiuid passageways 104, 108 and 105 intothe chamber103' and thence through passageway 75 and conduit 55 to the hydraulicfluid reservoir (not shown). At the same time, fluid in the chamber 72to the left of the piston 73 is exhausted through port 88 and conduit 55to the reservoir. In operation, pressure fluid may be supplied to unlockthe coupling of the present invention in a manner described in copendingpatent application, Serial No. 830,587, filed August 30, 1959, wherein apair 1 of tubing strings 35 and 36 (FIGURE 1) are inserted through arunning string or marine conductor 32 to supply pressure fluidselectively to conduits 55 and 56 leading to the coupling.

This patent application is a continuation of United States patentapplication, Serial No. 835,931, filed August 25, 1959, now abandoned.

I claim as my invention:

1. A pipeline coupling unit comprising (a) first and second matingmembers positionable in spaced or coupled relationship and having flowpassageways therethrough and adaptedto be positioned initially in spacedrelationship and approximate coaxial alignment,

(b) said first member being provided with a sealing surface around itsflow passageway for receiving a sealing surface of said second member(c) sealing means on one of said sealing surfaces adapted to sealbetween said sealing surfaces of the first and second members,

' (d) said second member comprising 7 a fixed tubular member adapted tobe aligned with said first member, s

a slidable tubular member outside and slidable relative to said fixedtubular member and concentric therewith,

actuating means engaging said slidable tubular member to move saidtubular member between retracted and extended positions to engage saidfirst mating member,

(2) said sealing surface of said second member being located on theextendable end portion of the slidable member, and

(f) aligning means carried by said slidable member and disposed radiallyfrom said sealing surfiace of the second member and engageable with thefirst member whereby said first and second members are movable fromapproximate to substantial alignment to permit co-engagement of thesealing sur-fiaces.

2. The apparatus of claim 1 including releasable latching means carriedby the slidable mem her and engageable with said first member to latchthe members in coupled relation.

3. The apparatus of claim 2 wherein the slidable member is adapted toconcentrically surround said first member and includes secondary sealmeans between the end thereof and the releasable latching means to sealand latch to said first mating member.

4. A pipeline coupling unit adapted to connect an underwater wellhead toan underwater pipeline, said coupling unit comprising first and secondmatingvmerrrbers having central flow 5 passageways therethrough adaptedto be initially positioned in spaced relationship and approximatecoaxial alignment and subsequently positionable in coupled relationship,said second member of said coupling comprising a fixedly-positionedcentral tubular member adapted to be aligned with said first member,sleeve means carried by said tubular member and having an end portiontelescopically extendible beyond the end of said tubular member into re-,leasa'ble sealing engagement with said first member,

actuating means carried by said second member and operatively-connectedto said sleeve means for moving said sleeve means into engagement withsaid first member,

annular resilient seal means carried on at least one surface of saidextendible end of said sleeve means and engageable in fiuidtight contactwith said first member, and

axially directed aligning means disposed radially from said seal meanson said second member for engaging said first member to bring said firstand second members into substantial axial alignment.

5. The apparatus of claim 4 including releasable locking means carriedby the extendible end of said sleeve means engageable with said firstmember. 6. The apparatus of claim 4 wherein, one of said members of saidcoupling being provided with seating means at the end thereof coaxialwith said central fiow passageway for receiving at least a portion ofthe adjacent end of said other member.

7. The apparatus of claim 4 including secondary seal means carried bysaid sleeve means between the extending end thereof and said lockingmeans and engageable in fluidtight contact with said first member.

8. A pipeline coupling unit adapted to connect an underwater wellhead toan underwater pipeline, said coupling unit comprising a first and secondmating members positionable in spaced or coupled relationship and havingcentral flow passageways therethrough adapted. to be positionedinitially in spaced relationship and approximate coaxial alignment,

said second member of said coupling comprising a fixedly-positionedcentral tubular member adapted to be aligned with said first member,sleeve means carried outwardly of and by said tubular member in fixedspaced coaxial relationship forming piston chamber means outside saidtubular member, piston means axially slidable relative to said tubularmember in said piston chamber,

said piston means being telescopically extcndible beyond the end of saidtubular member into releasable sealing engagement with said first memberand surrounding at least a portion of said first member when connectedthereto, resilient seal means carried on at least one surface of theextending end of said piston means and eugageable in fluidtight contactwith said first member, and conduit means through said second couplingmember for applying a pressure fiuid selectively to said piston means toconnect and disconnect said coupling. 7 9. The apparatus of claim 8including axially directed aligning means disposed radially from saidseal means on said second member for engaging said first member to bringsaid first and second members in substantial axial alignment.

10. A hydraulically-actuated pipeline coupling unit adapted to connectan underwater wellhead to an underwater pipeline, said coupling unitcomprising first and second mating members having central flowpassageways therethrongh adapted to be brought into spaced relationshipand substantially coaxial alignment, one of said members of saidcoupling being provided with a seating recess in the end face thereofcoaxial with said central flow passageway for receiving at least aportion of the adjacent end of said other member thereinto, said secondmember of said coupling comprising a fixedly-positioned central tubularmember adapted to be aligned with said first member, sleeve meanscarried outwardly of and by said tubular member in fixed spaced coaxialrelationship forming an annular piston chamber outside said tubularmember, annular piston means axially slidable on said tubular member insaid piston chamber, said annular piston means being of a lengthsufiicient so that one end thereof extends from said piston chamber andbeyond the end of said tubular member 'to connect operatively with saidfirst member, seal means carried on the extending end of said pistonmeans and adapted to be positioned in fiuidtight contact with said firstmember, releasable locking means carried by the extending end of saidpiston means engageable with said first member, and conduit meansthrough said second coupling member for applying a pressure fluidselectively to said piston means to connect and disconnect saidcoupling.

11. A hydraulicallyectnated pipeline coupling unit adapted to connect anunderwater wellhead to an underwater pipeline, said coupling unitcomprising first and second mating members ha 'ng central flowpassageways therethrough adapted to be brought into spaced relationshipand substantially coaxial alignment, said first member of said couplingbeing provided with a seating recess in the end face thereof around saidcentral flow passageway, and latching recess means on the outer surfaceof said first member for seating coupling locking means, said secondmember of said coupling comprising a fixedly-positioned central tubularmember adapted to be axially aligned with said first member, a sleevecarried by said second memher in fixed spaced coaxial relationshipoutside said tubular member, means closing the annular space betweensaid sleeve and said tubular member at one end thereof to form a pistonchamber, an annular piston axially slidable on said tubular member insaid piston chamber, said annular piston being telescopically extendiblebeyond the end of said tubular member to seat within said seating recessof said first member, seal means carried outwardly on the end of saidpiston adapted to be positioned in said seating recess, a collar fixedlycarried on the outside of said annular piston forming a tandem pistonmovable therewith outside said piston chamber, a tubular housing fixedlysecured on the outside of said collar and coaxial therewith, a portionof said tubular housing toward one end thereof being in telescopingslidable fluidtight engagement with said sleeve, the other end of saidtubular housing extending a distance sufficient to cover substantiallysaid first member of said coup-ling at the end of the piston stroke,locking dogs carried by said tubular housing and releasably engageablein the latching recess means on said first member of said coupling,spring means biasing said locking dogs to a locked position, a lockingand unlatching piston slidably carried by said tubular housing forselectively holding said locking dogs in locked position in said firstmember at one end of the piston stroke and subsequently unlatching andretracting said locking dogs at the other end of said piston stroke,conduit means through said second coupling member for applyingselectively a pressure fluid to first one of said pistons to connect andlock said coupling and then to the other side of said pistons to unlatchand disconnect said coupling.

12. A hydraulically-actuated pipeline coupling unit adapted to connectan underwater wellhead to an underwater pipeline, said coupling unitcomprising first and second mating members having central flowpassageways therethrough adapted to be brought into spaced relationshipand substantially coaxial alignment, said first member of said couplingbeing provided with a seating recess in the end face thereof around saidcentral flow passageway for receiving a portion of said second memberthereinto in fluidtight engagement, and latching recess means on theouter surface of said first member for seating coupling locking means,said second member of said coupling comprising a fixedly-positionedcentral tubular member adapted to be axially aligned with said firstmember, a sleeve carried by said second member in fixed spaced coaxi-alrelationship outside said tubular member, said sleeve being shorter thansaid tubular member, means closing the annular space between said sleeveand said tubular member at one end thereof, a seal-carrying annularpiston axially slidable on said tubular member in a piston chamberformed by the annular space between said sleeve and said tubular member,said annular piston being of a length suflicient so that one end thereofextends from said piston chamber and beyond the end of said tubularmember to seat within said seating recess of said first member, sealmeans carried outwardly on the end of said piston adapted to bepositioned in said seating recess, a collar fixedly carried on theoutside of said annular piston forming a tandem piston movable therewithoutside said piston chamber, a tubular housing fixedly secured on theoutside of said collar and coaxial therewith, a portion of said tubularhousing toward one end thereof being in 00- axial slidable fluidtightengagement with a portion of the outer surface of said sleeve at alltimes, the other end of said tubular housing having a chamber formed inthe Wall thereof, which wall extends a. distance suflicient to coversubstantially said first member of said coupling at the end of thepiston stroke, locking dogs normally extending inwardly from saidtubular housing into the latching recess means on said first member ofsaid coupling, spring means in contact with said locking dogs urgingsaid dogs to a locked position, a locking and unlatching piston slidablycarried within the chamber of said tubular housing for selectivelyholding said locking dogs in locked position in said first member andsubsequently unlatching said locking dogs therefrom, first conduit meansthrough said second coupling member for applying a pressure fluid to oneside of said annular and tandem pistons to connect said coupling, secondconduit means in communication with said first conduit means forapplying a. pressure fluid to said locking piston, spring-loadednormally-closed valve means in said second conduit means, said valvemeans extending beyond said collar and adapted to be opened by contactwith said first member of said coupling, third conduit means in saidsecond coupling member for applying pressure fluid to the other side ofsaid locking piston to unlatch said dogs, fourth conduit means in saidsecond coupling member for ap plying pressure fluid to the other side ofsaid annular piston to disconnect said coupling, valve means operativelyconnected to said locking piston for closing said fourth conduit meanswhen said dogs are in a locked position, guide means carried by at leastone of said coupling members on the cooperating ends thereof forbringing said first member in register with said second member as themembers are coupled together, and seal means carried between the innersurface of said tubular housing and the other surface of said firstcoupling member.

13. A hydraulically-actuated coupling system adapted to effect aremotely-controlled connection and disconnection of a pair of conduits,said coupling system comprising: first and second mating members, oneattached to each of the conduits to be connected, with a central flowpassage through each mating member in fluid communication with thepassage in the conduit to which it is attached; guiding and supportingmeans for guiding at least one of said mating members and supporting itin spaced relationship and in substantially coaxial alignment with theother mating member; said second mating member of said couplingcomprising a fixedly-positioned central tubular member adapted to bealigned with said first member, sleeve means carried outwardly of and bysaid tubular member in fixed spaced coaxial relationship forming anannular piston chamber outside said tubular member, annular piston meansaxially slidable on said tubular 11 member in said piston chamber, saidannular piston means being telescopically extendible beyond the end ofsaid tubular member in releasable sealing engagement with said firstmember, seal means carried by the extending end of said piston means andengageable in fluidtight contact with said first member, and conduitmeans through said second coupling member for applying a pres-References Cited in the file of this patent UNITED STATES PATENTSSaunders et a1 Apr. 22, 1952 COX et a1. Sept. 30, 1958

1. A PIPELINE COUPLING UNIT COMPRISING (A) FIRST AND SECOND MATINGMEMBERS POSITIONABLE IN SPACED OR COUPLED RELATIONSHIP AND HAVING FLOWPASSAGEWAYS THERETHROUGH AND ADAPTED TO BE POSITIONED INITIALLY INSPACED RELATIONSHIP AND APPROXIMATE COAXIAL ALIGNMENT, (B) SAID FIRSTMEMBER BEING PROVIDED WITH A SEALING SURFACE AROUND ITS FLOW PASSAGEWAYFOR RECEIVING A SEALING SURFACE OF SAID SECOND MEMBER (C) SEALING MEANSON ONE OF SAID SEALING SURFACES ADAPTED TO SEAL BETWEEN SAID SEALINGSURFACES OF THE FIRST AND SECOND MEMBERS, (D) SAID SECOND MEMBERCOMPRISING A FIXED TUBULAR MEMBER ADAPTED TO BE ALIGNED WITH SAID FIRSTMEMBER, A SLIDABLE TUBULAR MEMBER OUTSIDE AND SLIDABLE RELATIVE TO SAIDFIXED TUBULAR MEMBER AND CONCENTRIC THEREWITH, ACTUATING MEANS ENGAGINGSAID SLIDABLE TUBULAR MEMBER TO MOVE SAID TUBULAR MEMBER BETWEENRETRACTED AND EXTENDED POSITIONS TO ENGAGE SAID FIRST MATING MEMBER, (E)SAID SEALING SURFACE OF SAID SECOND MEMBER BEING LOCATED ON THEEXTENDABLE END PORTION OF THE SLIDABLE MEMBER, AND (F) ALIGNING MEANSCARRIED BY SAID SLIDABLE MEMBER AND DISPOSED RADIALLY FROM SAID SEALINGSURFACE OF THE SECOND MEMBER AND ENGAGEABLE WITH THE FIRST MEMBERWHEREBY SAID FIRST AND SECOND MEMBERS ARE MOVABLE FROM APPROXIMATE TOSUBSTANTIAL ALIGNMENT TO PERMIT CO-ENGAGEMENT OF THE SEALING SURFACES.